1. Field of the Invention
The invention relates to a preparation for shrinkproofing wool.
2. Description of the Prior Art
It is well known that wool, in the untreated state, shrinks and felts on being laundered in an aqueous liquor. In order to counteract this shrinking and felting, chemical treatments have already been recommended in which the structure of the wool is changed or in which finishes are used which contain resin which deposits on the surface of the wool fibers, enveloping these. By both processes, however, products are obtained whose so-called hand is regarded as unpleasant by the consumer.
It has also already been recommended that the shrinkage of wool of laundering be reduced by treatment with organosilicon compounds. Such compounds are described in British Pat. Nos. 594,901, 613,267, and 629,329. In accordance with these processes, the wool is treated with certain silanes.
A process for the prevention of shrinkage of wool is described in British Pat. No. 746,307, in which the wool fibers are finished with particular organopolysiloxanes. Admittedly, a certain degree of shrinkproofness is achieved by this process, however, this effect is not washfast.
German Offenlegungsschrift No. 1,769,249 discloses a process for the treatment of fibrous material, for example, of wool, in which organosiloxanes which contain mercaptopropyl groups are used in the form of an emulsion. With these compounds, however, it is merely possible to achieve a soil repellent effect. The compounds are not suitable for making wool shrink-resistant.
German Offenlegungsschrift No. 2,912,431 discloses an organopolysiloxane latex which consists of the product of the polymerization of a cyclic organopolysiloxane of the general formula ##STR1## in which R.sup.2 and R.sup.3 which may be the same or which may differ from each other, represent substituted or unsubstituted monofunctional hydrocarbon radicals with 1 to 10 carbon atoms and
n has an average value of 3 to 6, PA1 (A) an organofunctional trialkoxysilane of the general formula EQU (R'O).sub.3 SiRX, PA1 in which PA1 R' represents a monofunctional hydrocarbon radical with less than 7 carbon atoms or a group of the formula EQU --CH.sub.2 OC.sub.2 H.sub.5 or --CH.sub.2 CH.sub.2 OCH.sub.3, PA1 R represents a bifunctional hydrocarbon group with not more than 12 carbon atoms, and PA1 X represents an organofunctional radical of the formula EQU --NH.sub.2, --CH.sub.2 CH.sub.2 NH.sub.2 or --(CH.sub.2).sub.4 NH.sub.2 PA1 or radicals with the name of N-cyclohexylamino, N-phenylamino, N-aminoethylamino, N,N-dimethylaminoglycidyl, 3,4-epoxycyclohexyl, mercapto or methacrylo, PA1 (B) a surface active material, and PA1 (C) water. PA1 (A) a polydiorganosiloxane, PA1 (B) an organosiloxane with at least 3 silicon bonded hydrogen atoms and alkyl radicals with fewer than 19 carbon atoms as organic substituents, and PA1 (C) one or more cationic and/or nonionic emulsifiers. PA1 (a) 1 to 50 weight percent of organopolysiloxanes, which either consist, in the middle part of the molecule, of PA1 (b) 50 to 99 weight percent of water.
in the presence of
With such preparations, is is admittedly possible to influence the hand and, within certain limits, the wettability and the water repellency of the wool. However, as will also be shown in a comparison example, it is not possible to finish the wool with these latexes so that it will not felt.
German Offenlegungsschrift No. 2,725,714 describes a siloxane-in-water emulsion which contains
It is characterized by the fact that the polydiorganosiloxane (A) has a molecular weight of at least 2,500 and terminal OX radicals, X being a hydrogen atom, an alkyl radical with 1 to 15 carbon atoms or an alkoxyalkyl radical with 3 to 15 carbon atoms. At least two of the silicon bonded substituents of the polydiorganosiloxane are monofunctional radicals of carbon, hydrogen, nitrogen, and optionally, oxygen, which contain at least two amino groups and are linked through a silicon-carbon bond to silicon. Also, at least 50% of all substituents of the polydiorganosiloxane are methyl groups and the otherwise present substituents are monofunctional hydrocarbon radicals with 2 to 20 carbon atoms, and the emulsion additionally contains (D) magnesium sulfate and/or sodium sulfate.
This emulsion is intended to be useable for the treatment of goods made of keratinous fibers, for example, for the treatment of sweaters. It is a disadvantage of these emulsions and also of the diluted liquors prepared from them that the splitting off of hydrogen from the silyl hydrogen containing siloxanes is accelerated by the amino groups of the amino alkyl modified siloxane diols. This impairs and shortens the stability of the emulsions and of the diluted liquors. At the same time, the effectiveness of the liquor is reduced, as will also be shown by a comparison example below. Moreover, it turns out that especially bright and naturally colored wool yellows when treated with these products.
Accordingly, it was not possible to shrinkproof wool perfectly and entirely satisfactorily with the preparations of the state of the art.